Process of pyrolyzing and desulfurizing sulfur bearing agglomerative bituminous coal

ABSTRACT

THIS INVENTION DISCLOSES AN EFFICIENT ECONOMICAL CONTINUOUS METHOD OF PYROLYSING AND DESULRURIZING AGGLOMERATIVE BITUMINOUS COAL IN A TRANSPORT REACTOR TO RECOVER VOLATILE HYDROCARBONS AND HYDROGEN BY HEATING THE PARTICULAR COAL AND CHAR HAVING PARTICLE SIZES OF LESS THAN 65 MICRONS ENTRAINED IN AN INERT CARRIER GAS HAVING PYROLYSIS REACTOR RESIDENCE TIMES OF UNDER THREE SECONDS.

A. SASS ET AL PROCESS oF PYROLYZ ING AND DESULFURIZING SULFUR BEARINGAGGLOMERATIVE BITUMINOUS COAL Filed July 25, 1970 May 1973 U E @Kimm vmPROCESS OF PYROLYZING AND DESULFURIZING SULFUR BEARING AGGLOMERATIVEBITU- MINOUS COAL Allan Sass, South Pasadena, and Clem Finney and HarryMcCarthy, Claremont, Calif., and Paul Kaufman, Vienna, W. Va., assignorsto Occidental Petroleum Corporation, Los Angeles, Calif.

Filed July 23, 1970, Ser. No. 57,582 Int. Cl. C10b 57/00 U.S. Cl. 201-1716 Claims ABSTRACT F THE DISCLOSURE This invention discloses anetlicient economical continuous method of pyrolysing and desulfurizingagglomerative bituminous coal in a transport reactor to recover volatilehydrocarbons and hydrogen by heating the particulate coal and charhaving particle sizes of less than 65 microns entrained in an inertcarrier gas having pyrolysis reactor residence times of under threeseconds.

BACKGROUND OF INVENTION The use of 'uidized systems wherein a uidizedstream is formed of finely divided coal particles, heated char particlesand a carrier stream to pyrolyse the coal particles to extract thevolatiles therefrom is well lknown in the art. In such prior artprocesses the heated char particles and/ or the gas stream are utilizedto provide the requisite heat of pyrolysis to the coal particles with asupply of char continuously being produced upon pyrolysis of the coal inthe system. Such systems are ideally suited to the recovery of volatilesfrom agglomerative bituminous coal, since they are continuous processes,requiring relatively low capital outlays and can process large volumesof coal cheaply. Exemplary of such type processes is that disclosed inthe U.S. Pat. No. 2,608,526 entitled Coking of Carbonaceous Fuels issuedto W. A. Rex on Aug. 26, 1952.

However, when such prior art processes have been applied toagglomerative bituminous coal, problems have arisen due to theagglomerative nature of such coal. The agglomeration of the coalparticles causes severe blockages in the system and renders the systeminoperable. In recognition of the severity of this problem, theinventors in the U.S. Pats. 2,955,077 entitled Fluidized CarbonizationProcess for Agglomerative Coals issued to I. H. Welinsky, Oct. 4, 1960and 3,375,175 entitled Pyrolysis of Coal issued to R. T. Eddinger, Mar.26, 1968 disclose the use of a pretreatment of particulate agglomerativecoal to lessen the deleterious eiects of agglomeration. In these`processes the agglomerative particulate coal is preheated in aconventional uidized bed at temperatures ranging from 600 F. to 825 F.for periods ranging from 1 to 30 minutes to remove at least a portion ofthe yvolatiles from the coal so that the coal can be further pyrolysedto recover the volatiles therefrom. The requirement of preheatingagglomerative bituminous coals in these processes for relatively longresidence times imposes severe economic limitations on these processes.

SUMMARY OF INVENTION This invention discloses a continuous process forthe pyrolysis of agglomerative bituminous coal to recover the volatilestherefrom comprising forming a high velocity stream composed ofparticulate agglomerative coal, particulate char and a substantiallyinert carrier gas in a pyrolysis zone, such that the char and coalparticles are intimately admixed and entrained within the gaseousportion of the stream, the solids content of said stream in IUnitedStates Patent O ICC the zone ranging from about 0.1 to about 10.0percent by volume based upon the total volume of the stream in thepyrolysis zone, said stream at its initiation being made up of fromabout 5 to about 25 parts by weight of particulate coal having aparticle size of less than 65 microns and an initial temperature of lessthan 300 F., based upon the total weight of the coal and char beingutilized in forming the stream and from about to 75 parts by weight ofparticulate char having a particle size of less than 65 microns and aninitial temperature ranging from about 1150a F. to about 1600 F. basedupon the total weight of the coal and char being utilized in forming thestream; the residence time of said stream in the pyrolysis zone rangingfrom about 0.01 to about 3 seconds wherein the particulate coal isheated to a temperature ranging from about 900 F. to about 1200 F.;removing the products produced in the pyrolysis zone and separating thechar particles from the carrier gas and hydrocarbons produced uponpyrolysis of the coal.

In addition to the process for recovery of volatiles from agglomerativebituminous coal, we have also discovered that sulfur contamination canbe readily removed when coal is processed in processes similar to thisinvention or in similar processes for non agglomerative coals by theaddition of sulfur acceptors e.g., iron oxides, to the particulate coalprior to processing or by heating the products to high temperatures inthe presence of hydrogen upon removal of the products from the pyrolysiszone. Our novel process provides those skilled in the art with anefficient economical one step continuous process for the removal ofvolatiles from agglomerative bituminous coal with the added advantage ofproviding an eiiicient, economical method of desulfurizing coal.

BRIEF DESCRIPTION OF THE DRAWING The drawing shows in schematic outlinean arrangement of equipment for carrying out the novel processes of thisinvention.

DETAILED DESCRIPTION OF PREFERRED EMBODIMENT By the term high velocitystream is meant a stream of gas owing through a pyrolysis zone, e.g. apipe shaped reactor vessel, wherein the flow is turbulent in nature e.g.having a Reynolds ilow index number greater than 2000. Laminar ilow inthe pyrolysis zone must be avoided, as such a ow system would tend toseverely limit the productivity and rate of heat transfer within thepyrolysis zone. In the normal practice of this invention the char andcoal solids are introduced into the bottom or top of the pyrolysisvessel and the char and coal are rapidly intermixed in the carrier gasand dynamically contacted with each other and blown through the vesselto permit the requisite heat transfer to take place. The heat requiredto remove the volatiles can be provided all or in part from either thesensible heat in the gas or in the char particles.

The inert carrier gases found useable in this invention to effectuatethe prolysis of the coal particles must be non-reactive with the coal,char and hydrocarbons eX- tracted from the coal during pyrolysis. Thisgas stream should be free of air, oxygen, water, carbon dioxide and thelike as they have a very deleterious effect upon the proportion ofvolatiles extractable from the coal. Exemplary of gases suitable for useas carrier gases in our Invention are, nitrogen, argon, CH4, H2, carbonmonoxide and any other gas which will not deleteriously react with oroxidize the organic portion of the matter within the system.

The design of a particular system in which our process is to be utilizedwill of course have to conform to the process limits as heretoforestated in the summary of the invention. The vessel must be designed withfeed flow rates that will produce the requisite turbulence and heatingof the particulate coal. Such design parameters are well known to thoseskilled in the art.

It must be understood that this invention is designed for the use ofagglomerative particulate bituminous coal and that such coals are Wellknown to those skilled in the art due to their tendency to plasticizeand become sticky at relatively low temperatures i.e., 750-850 F. theterm agglomerative bituminous in our invention is meant of course toinclude all other coals which may be agglomerative. The coal particlesfound useable in our invention can be prepared by any conventionalmethod which will produce coal particles of the requisite size. Careshould be taken to see that the exposure of the coal particles to oxygensources are minimized to prevent oxidizing of the coal since suchexposure will have a deleterious eifect on yields from the process. Forthis reason we prefer to maintain the coal at temperatures below 300 F.prior to feeding it into the system as Well as to prevent agglomeration.

The particulate char is added to the particulate coal in our inventionboth to prevent agglomeration and to provide at least a portion of theheat required for pyrolysis. The selection of a particular char-to-coalweight ratio will of course be dependent both upon the heat transferrequisites of the system as Well as upon the degree of agglomerativenessof the coal particles. Since part of the heat of pyrolysis can besupplied by the carrier gas, the temperature, flow rate and residencetime in the reactor must be calculated by well known methods for aparticular system. In general for economys sake we prefer to utilize thechar particles for the main source of heat for the pyrolysis due totheir density and the beneficial heat transfer coeflicients built intothe system.

The system is essentially designed to heat the agglomerative coalparticles to a temperature ranging from 900 F. to 1l00 F. to remove themaximum amount of volatiles therefrom. The selection of a particulartemperature in this range will of course be dependent upon theparticular coal employed and the residence time of the coal particles inthe pyrolysis zone.

The el'nuent from the pyrolysis zone is composed of char, volatilizedhydrocarbons, product gas, and inert carrer gas. The char solids can bereadily separated therefrom by any conventional solids/gas separatorsuch as a cyclone separator and the like. The volatilized hydrocarbonsand carrier gas can be separated and recovered by conventionalseparation and recovery means.

By the term volatilized hydrocarbons as used in this application ismeant the product gases produced by pyrolysis of the coal and in generalthese consist of condensable hydrocarbons which may be recovered simplyby coutacting the product gases with condensation means andnoncondensible gases such as methane and other hydrocarbon gases whichare not recoverable by ordinary condensation means such as methane, etc.The product gas stream also contains undesirable gaseous products suchas CO2, H28 and water which should be removed from the product gasstream by conventional means such as chemical scrubbing, etc. After thecondensible hydrocarbons and the undesirable gaseous products have beenremoved from the product gases, the scrubbed gases can be utilized asthe inert carrier gas or at least as a portion thereof to contribute tothe overall efficiency of the system.

Initially the system will be started up by using char from othersources, but after coal particles have had their volatiles removed, theywill be useful as the source of 'char particles required by the systemand will be produced in such excess that they will be readily utilizablein further processing to provide new materials which eulnnc@ the tural,sscncmiss Qt 91.11' process such as .fuel

'4 for use in a power plant or a source of raw materials for thechemical industry.

The excess char particles produced by our novel process can readily bedegasied by heating them to temperatures ranging from about 1200 F. tol800 F. to yield a hydrogen-rich gas stream which is saleable as premiumfuel, or can be upgraded into pure hydrogen, or for hydrotreating theheavier volatilized hydrocarbons evolved during pyrolysis.

Char degasilication can be carried out in several ways which, insubstance amounts to indirect or direct heating. In direct heating, thechar is contacted with sufficient oxygen from a suitable source, such asair, to bring the stream by controlled combustion up to the desireddegasication temperature. This can be accomplished in a transportreactor similar to the pyrolysis reactor or in a uidized bed reactor.

Preferably, the char is degasifed by indirect heating which yields a gasstream containing '70 or more percent by volume hydrogen. This may beaccomplished in a reactor similar to a tubular heat exchanger in whichthe char is blown through the tubes in a dense or dilute phase and fuelis burned with air or another suitable source of oxygen in adjacenttubes to supply the heat required for degasication.

Alternatively, the same result can be accomplished by the combustion ofthe fuel in tubes located in a uidized bed of the char. After separatingthe char from the evolved gases, the char is cooled for ultimate use asa high grade fuel.

Where it is desired to produce a low sulfur char, sulfur reduction maybe accomplished during pyrolysis, superheating and/or degasication ofthe resultant char.

'One of the major problems faced in processing agglomerative bituminouscoal and other types of coal, is polution due to the presence of noxioussulfur compounds which are released upon processing. We have discoveredthat our novel process and similar processes can be efciently andeconomically adapted to processes for removal of sulfur found in coal.

When coal having substantial amounts of iron pyriteS (FeS2) is processedin our invention or similar processes, the (FeS2) is converted due tothe heating of the char and the pyrrhotite is readily removable from theproduct solids by magnetic separation means.

Desulfurization during pyrolysis may also be achieved by having a solidsulfur acceptor, such as lime, present in the zone during pyrolysis.Preferably, however, iron oxide is used as the sulfur acceptor. Thesulfur combines with the iron oxide to form pyrrhotite. Both aremagnetic and may be removed, in addition to any iron pyrite naturallypresent, from the product char by magnetic separation. ThisA canconveniently be accomplished with minimum cooling of the char toconserve the heat requirements for processing.

Desulfurization may also be achieved during pyrolysis 'by enriching thegas stream with hydrogen, preferably part of the hydrogen releasedduring degasiication. The hydrogen fed to pyrolysis zone reacts withsulfur to form hydrogen sulde which is later removed iby conventionalmeans such as scrubbing, hydrogen also enriches the volatilizedhydrocarbons. In the preferred embodiment of our invention we use acarrier gas containing at least 20 parts by volume of hydrogen basedupon the total volume of carrier gas used.

Desulfurization may also be achieved during superheating of the char byemploying as the transport gas, a gas enriched With hydrogen. This gasreacts with the sulfur in the char to achieve additional sulfurreduction of the product char. As with desulfurization during pyrolysis,the hydrogen employed may be obtained by the recycle of olf gases fromchar degasiiication bEOI or after purification,

afgaat-z3 Where it is desired to recover the sulfur from the productchar, the char which is already at an elevated temperature is merelyheated to about 2300 to 2800 F. at ambient pressures in thenon-oxidizing environment for periods up to about 20 minutes. Thisresults in substantial sulfur reductions from the char. In contrast tothis, conventional calcination of petroleum coke requires much higheroperating temperatures and longer residence time to achieve effectivedesulfurization.

When the char is degasified by indirect heating, maintaining pressure atfrom about 15 to about 100 p.s.i.a. and using a hydrogen-rich transportgas enhances additional sulfur removal during degasification. Underthese conditions char can be desulfurized as well as degassed withinreactor times of about ten minutes. This desulfurization can be achievedsince the inorganic sulfur had been essentially removed lby the sulfuracceptor in previous treatment.

A basic system which may be used to carry out the process of thisinvention is illustrated in the attached drawing. With referencethereto, the particulate agglomerative bituminous coal having a particlesize of less than 65 microns which is fed as such, or after comminuationduring processing for removal of inherent values such as iron pyrites,to cyclone separator when the particulate carbonaceous matter isseparated from its carrier gas which is recycled. The compactedparticles enter reservoir 12 for ultimate feeding to reactor 14, thefeed to which is controlled by valve 16. The char required for thepyrolysis is stored in vessel 18 and its feed to reactor 14 monitored bycontrol valve 20. When the char is superheated to provide the heatrequired for pyrolysis, reservoir 18 is suitably insulated or heated tomaintain the char at its preferred feed temperature. Feed fromreservoirs 12 and 18 are combined with inert gas supplied externally, orfrom another part of the process and fed to reactor 14 through line 8.Reactor 14 is generally a vertical tubular reactor. When processingagglomerative bituminous coal having excessive plasticity it may behelpful to use a reactor having porous Walls through which an inert gasis continuously passed to prevent sticking of pyrolyzed particles to thesurface of the reactor.

After pyrolysis, the char, volatilized hydrocarbons and inert transportgas are passed to cyclone 22 for separation of solids from the gases.Any fines which pass from cyclone 22 are separated in electrostaticseparator 24 for return to the char product which is collected inreservoir 26. Where iron oxide is introduced to the particles in reactor14 as a sulfur acceptor, there is positioned a magnetic separator eitherbefore cyclone separator 22 or between cyclone Separator 22 andreservoir 26.

Separation of the char from the gas is preferably carried out withouttemperature reduction to conserve the process heat. In addition,reservoir 26 is suitably insulated to prevent heat loss. The char whichis collected in reservoir 26 is preferably split into two streams whichsplit can be effectuated and metered -by valve 27. One constitutesrecycle char and is preferably fed to superheater 28, and the balancefed to degassing unit 30.

Alternatively, all of the char from reservoir 26 may be sent todegassing unit 30 where, as a consequence of degasification, it issuperheated to or above the temperature required for pyrolysis. Aportion is withdrawn asV product char and the balance returned toreservoir 36 for ultimate use as inert char in reactor 14.

When the char is passed to superheater 28, it is generally heated to asuperheat temperature of from about 1150 F. to about 1600 F. Heating maybe done directly by contacting the char with ambient or preheated airsupplied from preheater 32 and inducing controlled combustion. Heater 28may be a high velocity reactor similar to pyrolysis reactor 14 or afiuidized bed. It is preferred to conduct superheating at a temperatureno greater than about ll50 F. since above this temperature, evolution ofhydrogen from the char is initiated and the hydrogen essentially lost asit is greatly diluted -by the combustiou gases.

Preheated char is then passed to cyclone 34 for solidsgas separation andto high temperature char reservoir 18.

The balance of the char removed from collector 26 is pyrolysed char andis passed to degasier 30, shown here as a reactor in which the char ispassed in indirect contact with hot products of combustion and raised toa temperature of from about l200 F. to 1800 F. to dehydrogenate thechar. The char and the hydrogen-rich gas then pass to cyclone separator36 for solids-gas separation.

The hydrogen stream is passed to purification operations for removal ofhydrogen-sulfide and carbon dioxide to generate a hydrogen streamsuitable for use as a fuel for hydrogenation of hydrocarbons, anddesulfurization of the char.

Char is collected in vessel 38 and can be removed therefrom through line43 and valve 45 for ultimate use as a fuel for power plants or for useas char in pyrolysis portion of the system by being metered into theinert gas stream through line 41 and valve 39. Preferably, the char iscooled in several stages after degasification and before passage tostorage. The char may, for instance, be cooled to 1000c to l200 F. bycontact with Water or steam to generate, by reaction, additionalhydrogen and car-bon monoxide and/or carbon dioxide;

The gaseous stream from electrostatic precipitator 24 is passed to afirst condenser 40 where it is brought into contact with a water sprayto generally cool it to about 500 F. for condensation of heavyhydrocarbons and tar-like products which are separated from the gasStream. The gas stream is then passed through Waste heat boiler 42 andinto a second condenser 44 where lighter oils and water are condensedand separated into an oil phase and water phase. The water is recycledto condenser 40 and the oil decanted at the interface for recovery andsale or, where desired, for the processing.

The residual gas stream is then passed to absorber 46 where it isbrought into contact with conventional absorbents for carbon dioxide andhydrogen sulfide. The pregnant absorbent is then passed to regenerator48 where the hydrogen sulfide and carbon dioxide are separated to permitabsorbent recycle.

Hydrogen sulfide and carbon dioxide are then preferably passed to asulfur unit such as a Claus-type furnace for conversion to sulfur. Theefiiuent gases from absorber 46 are then sold as product fuel gas or allor a portion of the effluent returned to the system as inert transportgas.

EXAMPLE I The following example is given to illustrate the practice ofour invention. Commercial nitrogen was utilized as the carrier gas topass the agglomerative bituminous coal and char through the pyrolysiszone. The zone consisted of a pipe 10 feet long having an insidediameter of 1 inch which was wrapped in electrically powered heatingunits to provide the heat for pyrolysis. 2.3 pounds per hour of mixtureof char and coal particles having a maximum particle of 25 microns and aweight ratio of 3 parts char solids to one part coal solids.

The solids were heated to a temperature of 1025 F. in the pyrolysiszone. The ow rate of nitrogen through the zone during pyrolysis wasmaintained at 14 standard cubic feet per minute.

The system was operated for a period of one hour and both the productand the system were monitored to check for any deleterious effectsarising due to agglomeration of the coal in the system. Minimal effectswere noted but were so small as to permit the process to be carried outindefinitely without requiring steps to be taken to clean the pyrolysiszone. In fact the gas pressure differential EXAMPLE II To illustrate theeffect of the use our novel process in preventing deleterious effectsarising from the use of coal particles having relatively large particlessizes the following chart shows the results of four experiments carriedout in accordance with the practice of Example I supra.

TABLE 1 Experiment Number A B C D Particle feet; rate lb./min l0. 2. 12. 1 2. 3 Maximum size of particles in feed 4 150 50 25 N 2 flow rate(standard cubic tJmin 12. 6 13. 9 14. 0 14. O Inert particulate ma erChar Silica Silica Char Wt. ratio inert/coal particles. /1 5/1 5/1 3/1PytOlYSiS temp., F 1,000 1,000 1,000 1, 090

Premure drop as measured in inches of Water in pyrclysis zone Time,minutes:

EXAM-PLE IH The following illustrates the desulfurization of coal charswhich had been degasied at 1600 F. Two char samples were passed to athermal desulfurization zone at respective temperatures of 2540" F. and2740 F. The sulfur content of the product char as a function ofresidence time n the desulfurization process is shown in Table 2.

TABLE 2 Sulfur content of char,

wt. percent, at-

Time, minutes 2,540 F. 2,740" F.

EXAMPLE IV This example is given to show the eifectiveness of magnetictreatment of char to remove sulfur.

In this example samples of the unpyrolysed coal and pyyrolysed char fromExample I having a maximum particle size of 25 microns was run through aroll type high intensity magnetic separator. The magnetic separator wasa model 127, high intensity induced roll magnetic separator produced byCarpco Research and Engineering Corporation run under test operatingconditions of 3.0 amperes, with a splitter setting of 0, a drum speedsetting of 80, a separation gap between rotor and magnet of l/s inch anda particulate coal or char feed rate of 2.6 grams per minute.

The initial sulfur content of the unpyrolysed particulate coal was 2.55percent and the sulfur content of this particulate coal after it hadbeen passed through the magnetic separator was 2.56% the initial sulfurcontent of the pyrolysed char produced in Example I was 2.57% and afterthe char particles had been passed through the magnetic separator thedesulfurized char had a sulfur content of 2.0l%

It will be obvious to those skilled in the art that our novel processprovides an eicient economical process for lowering the sulfur contentof coal.

We have discovered that the yields of volatilized hydroarbons fromagglomerato@ bituminous coals which are produced in our process arerelatively sensitive to the pyrolysis temperature, and is optimum ofl,025 F. At this temperature approximately 36 percent by weight of thecoal is 4converted to volatilized hydrocarbons. This represents a yieldof synthetic crude oil of almost two barrels per ton of coal afterhydrogenating, which is significantly greater than other conventionalprocesses. The volatilized hydrocarbons produced in our process are muchricher in the valuable low boiling compounds than tars produced inconventional processes. For example, about 20 percent of the volatilizedhydrocarbons have a boiling point below 400 F.

What is claimed is:

1. A process for the pyrolysis of agglomerative bituminous coal torecover volatiles therefrom comprising:

(a) forming a high velocity stream composed of particulateagglomerati-ve bituminous coai, particulate char and a substantiallyinert, nonoxidizing carrier gas in a pyrolysis zone, such that the charand coal particles are intimately admixed and entrained within thegaseous portion of the stream, the solids content of said stream in thezone ranging from about 0.1 to about l0 percent by volume based upon thetotal volume of the stream in the pyrolysis zone said stream at itsinitiation being made up of from about 5 to about 25 parts by weight ofparticulate agglomerative bituminous coal having a particle size of lessthan 65 microns and an initial temperature of less than 300 F. basedupon the total weight of the coal and char in the stream, from about 95to about 75 parts by weight of particulate char having a particle sizeof less than 65 microns and a temperature ranging from between about1150 F. to about 1600" F. based upon the total weight of the coal andchar being utilized in forming the stream; the residence time of saidstream in the pyrolysis zone ranging from about 0.01 to about 3 secondswherein the particulate coal is heated to a temperature ranging fromabout 900 F. to about 1200 F. to yield volatilized hydrocarbons and charproducts;

(b) removing the products produced from the heating and separating thesolids portion thereof containing the particulate char produced thereinfrom the gaseous stream composed of volatilized hydrocarbons and carriergas; and

(c) separating and recovering the hydrocarbons from the gaseous stream.

2. The process of claim 1 wherein a portion of the solids produced bypassage of the particulate coal and char through the pyrolysis zone isheated to a temperature ranging from between about 1150 F. to about1600" F. and thereafter is utilized to form a portion of the highvelocity stream.

3. The process of claim 2 wherein the particulate char utilized in theformation of said stream has a temperature of 1150" F.

4. The process of claim 2 wherein the solids content of said stream is 3percent by volume based upon the total volume of the stream in thepyrolysis zone.

'5. The process of claim 2 wherein the stream contains parts by weightof char based upon the total weight of coal and char.

6. The process of claim 2 wherein the carrier gas is a hydrogen enrichedgas stream.

7. The process of claim 2 wherein the agglomerative bituminousparticulate coal contains sulfur and from about l to about 5 parts byweight of a particulate sulfur acceptor based upon the total weight 0fsulfur in the coal is admixed with the coal prior to forming the stream.

8. The process of claim 7 wherein the sulfur acceptor is particulateiron oxide.

9. The process of claim 8 wherein the sulfide of iron formed duringpyrolysis are magnetically separated from the products produced by thepyrolysis of the particulate coalv 10. The process of claim 2 whereinthe portion of the solids produced by passage of the particulate coaland char through the pyrolysis zone which is not recycled though thepyrolysis zone is heated in a degasication zone in the presence of aninert carrier gas to a temperature ranging between from about 1200o F.to about 1800 F. to form a hydrogen rich gas stream.

11. The process of claim 10 wherein the hydrogen rich gas stream isutilized as the inert carrier gas in the pyrolysis of the coalparticles.

12. The process of claim 10 wherein the degasilied char is heated to atemperature ranging between from about 2300 F. to about 2800 F. in thepresence of an inert carrier gas.

13. The process of claim 10 wherein the volatile hydrocarbons producedupon pyrolysis of coal are catalytically hydrotreated with at least aportion of the hydrogen rich stream.

14. The process of claim 1 wherein the agglomerative bituminous coalcontains sulfur and the inert carrier gas contains hydrogen.

15. A process of claim 1 in which the solids removed after the heatingare degasied and desulfurized by heating the solids to a temperatureranging between from about 2300 F. to about 2800 F. for a period of timeup to about 20 minutes in the presence of an inert carrier gas.

16. The process of claim 1 wherein the particulate coal is heated to atemperature of about 1025 F. in the pyrolysis zone.

References Cited UNITED STATES PATENTS NORMAN YUDKOFF, -Primary ExaminerD. EDWARDS, Assistant Examiner U.S. C1. X.`R.

ZCI-20, 22, 31; 48-210

